Generally, in a refrigerant-transporting hose used as a piping hose in an automobile engine room, a fluorine refrigerant such as Freon (R12) and alternative Freon (such as R-134a) is used. In recent years, since the regulation on transpiration of ozone layer depleting gas is tightened, requirements on refrigerant permeability of a refrigerant hose for an automobile have become strict; therefore, resin having high crystallinity such as polyamide resin is used as a material for an inner layer of a refrigerant-transporting hose. As such a refrigerant-transporting hose, for example, there is proposed a hose having an inner layer made of polyamide resin and an outer layer made of a polypropylene/butyl rubber alloy material, formed by bonding the both layers with an adhesive (see International Publication No. 97/31212).